isotope
an atom with the same number of protons but a different number of neutrons.
relative isotopic mass
mass of an atom of the isotope, relative to 1/12th of the mass of a carbon 12 atom
relative atomic mass
weighted mean mass of an atom of an element, relative to 1/12th ofthe mass of a carbon 12 atom
1st ionisation energy
the amount of energy required to remove one mole of electrons from onemole of atoms in a gaseous state
2nd ionisation energy
the amount if energy required to remove 1 mole of electrons from 1 mole of gaseous 1+ions
periodicity
a reqular repeating pattern of chemical or physical trends with increasing atomic number
Hydrocarbon
Molecule that only contains hydrogen and carbon
Functional group
An atom or group of atoms that are responsible for chemical reactions
Homologous series
This is a set of compounds that have the same functional group, similar chemical properties and physical properties that show a graduation (gradual change from one to the next)
Saturated
Contains single bonds only
Unsaturated
Contains at least one double bond
Displayed formula
Shows evert atom and every bond H-C-C-C-C-C-H
Structural formula
Shows the structure unambiguously CH3CH2CH2CH2
Skeletal formulas
Shows c-c bonds (and any functual group) /\/\/
Empirical formula
The simplest whole number ratio of atoms of each elements in a substance
Molecular formula
The actual number of atoms of each element in ONE MOLECULE . mr over emp
Structural isomer
Molecule that have the same molecula formulas but different structural formulas
hunds rule
electrons will fill orbitals on the same subshell singularly before pairing
paulis rule
electrons that occupy the sam orbitals (in pairs) have opposite spins
